非完整球体活塞高效率传动修形方法研究

以提高球形泵的机械效率和容积效率为目标，围绕非完整球体活塞几何结构参数与负载工况的动态耦合机制，开展活塞高应力区域轮廓的修形方法研究。首先，基于活塞非完整球体结构，建立球形泵排量理论模型，试验研究不同排量及活塞角下球形泵机械效率和容积效率变化规律。其次，探究不同转速、流量、介质压力等负载工况对活塞滑动接触力的作用规律。构建考虑活塞结构参数及运转特征的动态承载接触分析模型，综合分析旋转载荷等参数对其传动效率的影响规律。然后，基于旋转坐标系建立活塞的变形协调方程，确定活塞轮廓修形部位空间区域坐标，确定修形曲线和修形量。最后，开展球体活塞高效率传动的修行方法试验研究，对比修形前后机械效率和容积效率的变化规律，验证所提修形方法的正确性与有效性。本项目研究成果可为高机械效率和容积效率的球形泵设计提供理论基础支撑。

The profile modification methodology will be utilized to improve both mechanical and volumetric efficiency of the spherical pump, by considering the coupling mechanism between operational condition and geometrical configuration of the sphere piston, the maximum contact stress zone will be captured and modified. Both theoretical and experimental approaches will be applied in this proposal. Firstly, the spherical pump displacement equation is established by considering the geometrical configuration of piston, the mechanical and volumetric efficiency of spherical pump under different displacements and piston angles will be experimentally investigated. Secondly, the operational impacts of rotation speed, flowrate, hydraulic pressure on contact stress will be considered. Based on numerical simulation and analytical contact mechanics, the dynamic contact model between partial sphere piston and cylinder will be built, to analyze the impact of rotation loads on time-domain contact stress. Then, piston deformation coordination equation will be formulated by using the space rotating coordinate system, to capture the high-stress and modification domain, determine the modification curve and amount. Finally, experimental test will be conducted to investigate the improvement of both mechanical and volumetric efficiency after profile modifying of sphere piston, to evaluate effectiveness and correctness of the proposed profile modification methodology. The ultimate purpose of this proposal is to provide basic principle and methodology to design the high mechanical and volumetric efficiency spherical pump.